Tungsten Disulfide Saturable Absorber for Nanosecond Pulses Generation

摘要

We fabricated tungsten disulfide (WS2) based saturable absorber (SA) and use this to passively mode-lock an Erbium-doped fiber laser (EDFL) and produce nanosecond pulses train. The SA was obtained by repeatedly dropping the WS2 solution onto microfiber to form a nanosheets layer after drying process. A stable nanoseconds pulses train operating at 1560 nm was successfully achieved by inserting the developed SA device into a 206.4 m long laser cavity. A stable 409 ns pulse is obtained at repetition rate of 965 kHz as the pump power was raised above the threshold of 150 mW pump power. The maximum pulse energy of 1.79 nJ was obtained at 193 mW pump power. The generated pulses are consistent and stable, which useful in many practical applications.